The specific aims are to determine the feasibility of creating an integrated knowledge system practicing physicians can easily and rapidly access for information from the medical literature needed to support their diagnostic and therapeutic decisions, and to assess the utility of such a system to physicians. The knowledge base will be a combination of core knowledge (derived from the leading most authoritative subspecialty textbooks available) plus integrated updating information from the current literature. It will be available online, accessible with a wide variety of terminals or microcomputers. A natural language capability allows the physicians to type an inquiry in natural English and quickly receive paragraphs provided in order of their ranked relevance to the query. The system also allows browsing within the hierarchical contents to find treatment of information at different levels of detail, or to obtain contextual understanding. Successful demonstration of its usefulness to physicians will lead to coverage of all of oncology, all of gastrointestinal disease, and then to coverage of internal medicine. The commercial importance of this innovation lies in its potential for becoming the first and routine source of knowledge acquisition for most practicing physicians.